This invention relates to a heat detection and alarm apparatus, and more particularly, to a plurality of heat sensitive conduits having sealed end portions in which a fluid is maintained at a preselected pressure therein so that the conduits rupture when exposed to an undesirably high temperature to actuate an alarm and discharge the fluid.
Fire protection systems, and particularly fire sprinkler alarm systems, as illustrated and described in U.S. Pat. Nos. 941,048; 2,166,264; 2,880,808; 2,891,625 and 3,180,422, are well known in the art and generally include a water conduit having one end portion communicating with a source of water under pressure. One or more sprinkler heads are supported by the water conduit and are operable when exposed to heat above a desired level, to release a closure plug from an outlet opening of the sprinkler head to allow water, under pressure, to flow therefrom. In combination with the control valve, an electrical switch, responsive to the fluid pressure through the sprinkler head outlet, actuates an electrical alarm circuit. In this manner, an alarm is given almost simultaneously with the actuation of one of the sprinkler head assemblies.
In each of the above enumerated patents, the sprinkler head assemblies are supported by the conduit that is connected to a source of water under pressure and is removed a substantial distance from the object to be sprayed. In most cases, the sprinkler head assemblies are positioned at the ceiling level. Therefore, a substantial increase in the temperature of any object on the floor is required before the sprinkler head is actuated and the fluid discharged to reduce the temperature of the object or extinguish a flame. This is an undesirable feature, particularly because the sprinkler head is not actuated until the object has reached the combustion temperature. As a result, an object located substantially remote from the sprinkler head assemblies can ignite without actuating the assemblies and not until the temperature in the area adjacent the assemblies reaches an excessive level is the assembly actuated. At this stage, substantial damage has already occured.
There is a need for a heat detection and alarm apparatus that is adaptable to detect temperatures in excess of a preselected temperature and actuate an alarm to indicate the occurrence of the alarm condition and simultaneously discharge a flame retardant material to reduce an excessive temperature or extinguish a fire. While it has been suggested by the prior art systems to provide heat sensitive sprinkler head assemblies that are actuated, upon the occurrence of fire, to discharge a fire extinguishing spray, none of the systems permit the detection of an undesirably high temperature by location of a detection device in substantially abutting relation with the object to be monitored.